NPM (nginx_app_1) is connected to each stack's own default network by hand, not to a shared docker_default. Drop the unused external `proxy` network from the compose file; nginx just lives on dmtools_default. setup.sh now connects NPM to it (no-op if already connected) and prints the proxy-host settings. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>